Section 7 Current Protection; Four Step Phase Overcurrent Protection Oc4Ptoc(51/67); Identification; Application - ABB REB670 Applications Manual

1MRK 505 337-UUS -
Section 7
7.1
7.1.1
7.1.2
Application manual
Current protection
Four step phase overcurrent protection
OC4PTOC(51/67)

Identification

Function description
Four step phase overcurrent protection
3-phase output

Application

The Four step phase overcurrent protection 3-phase output OC4PTOC (51_67) is used in
several applications in the power system. Some applications are:
• Short circuit protection of feeders in distribution and subtransmission systems.
Normally these feeders have radial structure.
• Back-up short circuit protection of transmission lines.
• Back-up short circuit protection of power transformers.
• Short circuit protection of different kinds of equipment connected to the power
system such as; shunt capacitor banks, shunt reactors, motors and others.
• Back-up short circuit protection of power generators.
If VT inputs are not available or not connected, setting parameter
DirModeSelx (x = step 1, 2, 3 or 4) shall be left to default value Non-
directional.
In many applications several steps with different current pick up levels and time delays are
needed. OC4PTOC (51_67) can have up to four different, individual settable, steps.The
flexibility of each step of OC4PTOC (51_67) is great. The following options are possible:
IEC 61850 IEC 60617
identification identification
OC4PTOC
TOC-REVA V2 EN
Section 7
Current protection
ANSI/IEEE C37.2
device number
51_67
161